Titon -
Filtering Out the Good from the Bad

Diesel Pollution - Air Pollution - MVHR System - NO2 Filters

With diesel pollution stories constantly in the news, it
has raised questions as to whether ventilation companies are
actually doing anything to address this concern. However,
new products are now emerging all the time and, even though
some are not proven in the market, it indicates the issue is
slowly being recognised - and a resolution may not be too
far away. Tyson Anderson, Sales & Marketing Director at
Titon explains, only models adhering to the necessary health
standards and Building Regulations should be considered.

In order to ease people’s minds about air pollution,
manufacturers and specifiers need to investigate how to
successfully combat it, as people’s health and lives should not
be compromised. There is evidence that high levels of NO2 can
inflame the airways in the lungs and, over a long period of
time, affect their functionality. People with asthma are
particularly affected, while NO2 can also cause other
respiratory problems, immunity to infections such as bronchitis
plus, in some cases, heart disease. As a result, it is becoming
imperative to design cost effective ventilation systems to cope
with the increased potential for air pollution. Consequently,
MVHR manufacturers are continually looking to develop products
to help combat such pollutants and improve air quality inside
the home.

The issue has now come to a head, with DEFRA estimating NO2
pollution causes up to 23,500 premature deaths a year (UK), with
traffic pollution contributing to the rising number of children
with asthma. Their data reveals almost 3,000 schools and many
planned homes are in areas breaching WHO (World Health
Organisation) air pollution limits this includes levels of NO2
above the stringent levels set out in the EU Directive
2008/50/EC – European Union Air Quality and Clean Air for Europe
2008. Such has been the concern that parents are now being fined
for not switching off their engines when picking up children
from school (Road Traffic (Vehicle Emissions) Regulations 2002)*
and fines rising to £80 in areas such as Westminster are being
issued; but is this enough, or does more need to be done?

It has already been highly publicised that indoor air quality
can be significantly improved via effective ventilation. Indeed,
by specifying MVHR System 4, moisture and airborne contaminants
will be removed, resulting in a healthier indoor environment for
occupants. In addition, there are also now specially designed
NO2 filters which can be added to an MVHR system and remove
pollutants being produced by diesel engines. These pollutants
include sulphur dioxide, hydrogen sulphide, hydrogen chloride
and chlorine. NO2 filters also help combat ammonia odours, while
absorbing VOCs and solvents.

From a legislative perspective, it is important any NO2
filters installed conform to the EU Directive 2008/50/EC (lAKA
the Clean Air for Europe programme or the CAFE Directive). This
programme was launched with the aim of developing a long-term,
strategic and integrated policy to protect against significant
negative effects of air pollution on human health and the
environment.

Filter units also need to comply with Part F (ventilation) of
the Building Regulations – especially the pages relating to
ADF’s performance criteria for dwellings (also applicable to
offices) stating that exposure to nitrogen dioxide (NO2) should
not exceed 288 μg/m over a one-hour average, and 40 μg/m over a
long-term average. However, interestingly, ADF doesn’t stipulate
that filters are a necessity; perhaps this needs to be
reconsidered, following all the recent findings concerning air
pollution?

NO2 filters – such as Titon’s own, award-winning Trimbox –
incorporate balanced flow technology to reduce NO2 to an
acceptable mean concentration level of 40µg/m3 while improving
indoor air quality. (Indeed, independent tests have demonstrated
such units to absorb 95% of NO2 not only in normal, continuous
ventilation mode but also at boost or higher ventilation
rates.)** These units can be installed in both intake and supply
ducting. Additionally, they can be used in small to large
dwellings, provided they are able to operate with variable
airflow.

However, we are now seeing an increased amount of
manufacturers offering many different NO2 filters, but these are
not necessarily as effective as other models on the market. Some
products are incorporating large carbon filters to adhere to
dwell time which increases airflow to achieve absorption rate,
for example; however, these can only go on to large and
cumbersome units – which results in it being costly and awkward
for installation.

A healthy ventilation strategy with adequate filtration is
crucial. After all, buildings are essentially acting similarly
to a lung - drawing in polluted air from outside air before
breathing out processed and filtered indoor air. While we have
known for many years the benefits of a successful MVHR strategy,
we now need to extol the virtues of adding high quality NO2
filters to these systems to ensure occupants remain fit and
healthy for the foreseeable future.

**Source: All performance data for the new filters has been
derived by independent testing at a UKAS recognised test house.
The testing regime was carried out to the World Health
Organisation’s and European Union standards. The test report
concludes that: "Both filter units performed very well, with
nitrogen dioxide filtration performances of approximately 98%
being achieved".